Coating for transfer paper



Patented Feb. 20, 1923.

' UNITED STATES JOHN H. RAVEN, or CHICAGO, rumors.

coarme ron TRANSFER PAPER.

No Drawing.

To all whom it may cpncern:

Be it known that I, JoHN H. RAVEN, a citizen of the United States, and aresident of the city of Chicago, in the county of 'Cook and State of Illinois, have invented'a new and useful Coating for Transfer Paper: and I do hereby declare that the following full. clear. and exact description of the same.

In the making of lithographs the design upon a stone or plate in lithographic ink or color is handled by means of a paper coated v with a suitable adhesive. This paper. which is known as transfer paper, is applied to the stone or plate so that the design is reproduced thereon. For commercial work it is very soft and-tough paper such as India paper or rice paper. but for color work other paper may be used. After it has been applied to the stone so as to receive the design, it is removed and fastened to a sheet known as the layout sheet. The pattern upon the stone can thus be repeated a number of times upon the layout sheet, a separate sheet of transfer paper being used for every repeti-' tion of the pattern so that the layout comprises a foundation'sheet of ordinary paper, having a number of pieces of transfer paper thereon, the coated side of the transfer paper being away from the foundation sheet and the paper being secured to-the foundation sheet in any convenient way such as pricking with a needle.

The layout sheet with the transfer paper thereon is then put to one side until a convenient time for the printing. When this time arrives, the first step is to apply the layout sheet to the zinc, stone or other plate that is to be used for printing, the adhesive side of the transfer paper being next to the stone or plate. By the proper application of pressure the pattern is then made to appear upon the stone or zinc. Then pulling the transfer paper ofi' leaves ink on the stone or plate in the desired pattern, so that the plate may be etchedin any of the usual ways.

In this process, the time during which the layout sheet may be put aside has heretofore been limited by the character of the coating upon the sheet, particularly in hot Weather. If an attempt is made to keep the layout sheet too long before applying it to the stone or plate, it will fail to adhere and the pattern thereon will not be properly reproduced. The character of the adhesive used the protective Application filed August 12, 1922. Serial No. 581,544.

has also limited the number of layout sheets that can be piled upon each other, because if too large a number are so piled they will stick to each other and the patterns on them will thus be lost.

It is an object of the present invention to produce a transfer paper so coated that the layout sheet may be kept much longer than heretofore. even in hotand damp weather.

It is a further object of this invention to produce a transfer paper with a coating that shall maintain its necessary adhesive qualities as long as the ink used thereon remains fresh enough to be transferable.

It is a further object of this invention to produce a coating for transfer paper which shall be made without the use of dextrine or of glue,v gelatine, or other product of animal nitrogenous matter.

It is a further object of this invention to produce a coating for transfer paper which shall be made wholly of starchy or fari'naceous material except for the addition of an. antiseptic, such as salt.

It is a further object of this invention to prepare a coating for transfer paper which shell be free from any tendency to become lumpy or granulated, and so will continue to, produce a uniform smooth coating.

It is a further object'of this invention to produce a transfer paper that shall require a considerable pressure to make it adhere to other sheets so that they may be piled higher than has h tice.

It is a furtherobject of this invention to prepare a material for coating transfer paper which will yield a coating that will maintain its adhesive qualities fora long period. 1

Other and further objects of this invention will be apparent from the disclosures in the following specification, which sets out a preferred form of the invention.

In the preparation of the material for coating transfer paper, I take two ounces of table salt, dissolve the same in a pint of water, and let the solution stand for at least twenty-four hours so that all of the salt is completely dissolved. .I then make'a mixture of nine ounces of starch retofore been the prac- 10! (either corn,

wheat, potato or other starch) and five paper and smoothed lo a coating machine I proportion of glycerine a thick paste art.

stone or plate while still fresh, the

even longer than the'ink of the.

to which ll add twelve ounces of pure glycerine. The hatter is then stirred until thoroug' ly mixed and cool enough to handle in appyling it to the paper. Preferably the hatter is strained through a line sieve while cooling.

The resulting mixture will he a batter of 'a consistency that will drip from a mixing spoon but will not quickly flow therefrom. The hatter is spread over the surface of the or by the worlmans orearm in the manner well The paper is then ready to apply at once to the stone or plate. lif not at once thus applied, the paper will still be fit for use even if kept some weeks in Warm weather. ln cool weather it will keep indefinitely. lt can he shipped in mailing tubes to he used by lithographers at distant points.

If the transfer paper is applied to the layout sheets can he kept in piles of more sheets than heretofore and even in warm weather the adhesive will continue in workable condition much longer than heretofore, and design will.

lit is of course understood that the proportion of waterjand glycerine must be varied to correspond to the weather, a smaller being used in damp weather. i am aware also that proportions of the other ingredients may be varied through a wide range and that the details of the several steps of the process can be changed without departing from of this invention, and I therelargely the spiritfore do not wish to limit the patent granted hereon otherwise than is necessitated by the prior art.

I claim as my invention: 1. A coating for lithographic transfer paper comprising from one-third of an ounce to one pound flour, one pound starch, from one-half to twenty ounces salt,'from two to understood by those skilled in this inseam fifteen quarts water, and from three to twentX fluidounces glycerine. 2.

paper comprising a mixture of one pound starchy lution of common salt containing from onefourth of an ounce to the pint to saturation, and from eight to thirty ounces of glycerine.

3. A- coating for lithographic transfer paper, comprising a mixture of starchy material, a solution of common salt and glycerine in substantially the proportions speci fied, said mixture being free from nonstarchy adhesives.

4:. A process of coating paper to prepare a transfer paper which consists in dissolving common salt in water from one-fourth of an ounce to the pint to saturation, permitting' the solution to stand until the salt has completely dissolved, making a paste of flour, starch, from one-thirtieth to'twice as much flour as starch, tion' of salt, from one-halfto four pounds of the d material to a gallon of liquid, adding g ycerine to the resultant mixture in amount dependent on the weather, and applying the result to one surface of the paper. Y

5. A transfer paper coated with adhesive material which will keep its adhesive properties for a period lithographic ink to dry.

6. A transfer paper comprising'a sheet of paper coated on one side with an adhesive compound consisting of from one to twenty ounces flour, two pounds starch, sufficient water to form a thin paste,"glycerine and two to fifteen ounces salt, Without the admixture of animal adhesive substances.

In testimony whereof I have hereunto subscribed my name in the presence. of two coating for lithographic transfer I I 5O material, one to two pints of a s0-- water, andthe solu- 

